Efforts by Pfizer to bolt to the greener tax pastures of the U.K. point to "tremendous problems" with the U.S. corporate tax structure, Sen. Bob Corker said Thursday.
If Republicans were to retake control of the Senate in November's midterm elections, corporate tax reform "might actually pass as a standalone," the Tennessee Republican said in a CNBC "Squawk Box" interview.
"I think there are enough thoughtful Democrats that realize that this is really problematic," he added.
New York-based Pfizer is trying to push through its unsolicited $106 billion offer to buy U.K. rival AstraZeneca. If successful, the U.S. drugmaker could move its corporate headquarters to Britain to save billions of dollars in taxes.
Meanwhile, Sen. Carl Levin, D-Mich, said he's working on legislation to prevent these so-called corporate inversions.
While saying he didn't know the details of what Levin was pursuing, Corker said: "If you have the concept, 'No American company can move,' I just can't imagine something like that passing."
"You have to be careful around here," Corker warned. "You have to pay attention because sometimes emotional things can happen on the floor which make absolutely no sense for the long haul."
Levin is the chairman of the Senate Permanent Subcommittee on Investigations, which has held hearings designed to shed light on the legal efforts of American companies to avoid U.S. taxes.
Corker was also optimistic that the Senate Banking Committee would pass a bipartisan housing finance reform bill. "I think we no doubt laid the groundwork for the future."
As a banking committee member, Corker and Sen. Mark Warner, D-Va., introduced the original bill that served as a template to phase out Fannie Mae and Freddie Mac with a privately capitalized system that preserves market liquidity and protects taxpayers from future downturns. Ten other senators are co-sponsoring the effort.
"This bill would move us to a situation with a lot of capital and a lot of competition," Corker told CNBC.
After Fannie and Freddie ran into trouble in the midst of the 2008 financial crisis, the government put forward $187.5 billion to bail them out. Lawmakers from both parties want to revamp the $10 trillion mortgage market to make it less likely taxpayers will ever be put on the hook again.
"There's tremendous consensus that we need a lot more capital in the system. And we don't want our system to be a duopoly where it's basically almost like a Russian arrangement," said Corker.
Corker, the ranking Republican on the Senate Foreign Relations Committee, also said he's disappointed with the way President Barack Obama has handled Russian President Vladimir Putin's moves in Ukraine.
"We have done nothing. Since we announced the sanctions and implemented the sanctions, the Russian stock market is up," Corker told CNBC. "These were nothing but tweaks."
He said he advocated hitting important Russian companies and sectors with sanctions. "I just don't get it, why we're willing to [continue] moving the red line."
The U.S. and the European Union have stopped short of imposing broader sanctions on Russia's economic sectors, but the president and German Chancellor Angela Merkel that they would move to harsher penalties if Russia disrupts Ukraine's presidential election—set for May 25.
But Corker remains concerned.
"Putin still has forces on the border, which are intimidating. I think everyone knows that he's fomenting through black-ops lots of problems inside eastern Ukraine," Corker said.
—By CNBC's Matthew J. Belvedere. Reuters and The Associated Press contributed to this report.