Republican presidential candidate Sen. Ted Cruz, R-Texas, did his best Donald Trump impersonation Friday, dramatically calling out his own party leader as a “liar.”

It’s been almost impossible for most of the Republican presidential hopefuls to get any airtime since Donald Trump transformed the cable news networks into his latest unavoidable “Trump” billboard, so on Friday, Sen. Ted Cruz, R-Texas, took an unusual step to bolster his conservative credentials and wrestle the spotlight back in his direction: He called his own party leader a “liar.”

Repeatedly.

Cruz’s message on the Senate floor was on a complicated topic of little interest except to the most hardened partisans: He accused Senate Majority Leader McConnell, R-Ky., of lying to him and other senators about offering an amendment on the controversial-among-conservatives Export-Import Bank, a government agency that provides financing to American companies trying to send goods abroad that might not get loans from private banks. The authorization for the bank has already expired, and Republicans would like to make sure it’s not renewed. But the Senate now is gearing up to vote Sunday on an amendment to revive the bank as part of its consideration of a long-term transportation bill currently before it.

If the actual issue is down in the legislative weeds, Cruz’s delivery and intention could not have been more geared to the broad media spotlight. Cruz dramatically accused McConnell of breaking a promise to him but also of being beholden to special interests and no better for conservative interests than his Democratic predecessor.

“Today is a sad day for this institution,” Cruz said, opening what would become a 20-minute tirade on the floor. “The Senate operates based on trust. Whether we are Democrats or Republicans, these 100 senators have to be able to trust that when a senator says something, he or she will do it. Even if we disagree on substance, that we don’t lie to each other.

“The majority leader looked me in the eye, and looked 54 Republicans in the eye. I cannot believe he would tell a flat-out lie. And I voted based on those assurances that he made to each and every single one of us,” he continued. “What we just saw today was an absolute demonstration that not only what he told every Republican senator but what he told the press over and over and over and over again was a simple lie.”

Of course, it has been long expected McConnell would offer a vote on Export-Import Bank reauthorization before August, and as recently as Tuesday the leader said he planned to allow a vote on the agency as part of the process of voting on the pending transportation legislation.

Just as striking is that Cruz recently said he’s “not interested in Republican-on-Republican violence,” when asked to condemn Trump’s remarks disparaging undocumented immigrants from Mexico. Yet he used the words “lie” and “lying” five times over the course of several minutes Friday — a once-verboten move in the staid institution of the Senate — about another Republican.

It revealed a truth about Cruz: He wasn’t interested in avoiding a confrontation wtih Trump just because Trump is a fellow Republican. Cruz was interested in defending a conservative whose supporters could be up for grabs later on in the campaign, because criticizing other GOP politicians is old hat.

Cruz, pictured earlier this week, at a protest in Washington. (AP Photo/Luis M. Alvarez)

The attack on McConnell Friday is just the latest example of Cruz’s campaign against Republican authority, a campaign that has been successful for him at the grassroots level since he was elected to Congress in 2012 but that now sees a crowded field of other conservatives vying for the same space.

He would not endorse the 2014 reelection bid of the senior senator in his own state, No. 2 Senate Republican John Cornyn of Texas — a move that has closed off to him some of the bigger wallets in the traditional fundraising destination of Dallas. Earlier in that same election cycle, he helped a powerful conservative group, the Senate Conservatives Fund—which ran ads against incumbent GOP senators, including McConnell—by taping anti-Obamacare ads that aired nationwide and put pressure on Republicans in tight primaries. His affiliation with the group caused tension with colleagues who believed conflicted with his position as vice chairman of the official campaign wing of the Senate GOP.

Now that an even more attention-grabbing critic than he has come on the playing field, the question is whether Cruz’s accusation of congressional double-crossing about a failed amendment can compete with Trump’s trips to the U.S.-Mexico border and near-constant cable news grandstanding.

Cruz tried to turn his complaint about the Export-Import Bank into a larger point about politics, saying that establishment Republicans like McConnell are no better than Democratic leaders like Harry Reid of Nevada.

“You know who doesn’t have lobbyists? A factory worker who just wants to work and provide for his or her children. They don’t have lobbyists. And so what happens? Career politicians in both parties gang up with giant corporations to loot their taxes and make it harder for people who are struggling to achieve the American dream,” Cruz said. “Coal miners … they don’t have lobbyists who are representing them here, the individual miners, while the majority leader teams up with the Democratic leader to take from their paychecks to fund giant corporations. It is wrong, and it is corrupt.”

He also claimed McConnell’s vote on repealing Obamacare, which is scheduled to happen with the bank vote, was an “empty” gesture because he would not allow a vote on a Cruz amendment that would take away employer contributions to congressional workers’ health care plans. McConnell “doesn’t want to end the cronyism for members of Congress any more than end the cronyism for giant corporations who enrich themselves at the expense of the American people.”

Cruz’s performance on Friday could be a preview for his plans this fall, however, as government funding is set to expire in September, and Cruz’s Senate incumbency provides him at least one advantage over other conservatives: He can literally threaten government shutdown in the name of his conservative bonafides and as a tool to fundraise. Which is what he did in 2013.

No matter how Cruz attempts to proceed, he’s certainly torched what remaining goodwill he had with his own leader — if there was any — and he’s unafraid to wage a personal “us versus them” war within the walls of the Senate chamber, when “them” is his own colleagues.

It makes for interesting political theater, but maybe still not as interesting as Trump’s.

Update: the post has been clarified to further explain Cruz's involvement with the Senate Conservatives Fund