WASHINGTON — Sen. Susan Collins said she will vote against Judy Shelton’s nomination to the Federal Reserve Board, raising the stakes of a political fight around one of President Donald Trump’s controversial picks for a seat on the central bank.

Collins joined Sen. Mitt Romney, R-Utah, in opposing Shelton’s nomination, which is slated to go for a vote before the full Senate. Collins and Romney alone can’t derail Shelton’s advancement, but the margin is getting thinner for Shelton, who is known for her outspoken criticism of the Fed and her advocacy for a return to the gold standard.

“I have serious concerns about this nomination,” Collins said in a statement Monday. “In her past statements, Ms. Shelton has openly called for the Federal Reserve to be less independent of the political branches, and has even questioned the need for a central bank. This is not the right signal to send, particularly in the midst of the pandemic, and for that reason, I intend to vote against her nomination if it reaches the floor.”

If the Senate’s Democrats and Independents all vote against Shelton’s nomination, her confirmation could be doomed if she looses the support of more than three Republicans.

Typically, the process for confirming Fed governors does not fan political flames or depend on such thin party margins. But Shelton’s nomination has been rocky from the start, including well before the coronavirus pandemic put sharp focus on the Fed.

In past remarks and writings, Shelton, who advised Trump’s 2016 presidential bid, has said the Fed harnesses too much power and should be reined in. Shelton has also called for a return to the long-abandoned gold standard, which her critics say make her an outlier when it comes to monetary policy.

Last week, the Senate Banking Committee voted 13 to 12 to narrowly approve Judy Shelton’s nomination. Earlier this year, multiple Republicans on the banking panel expressed reservations about Shelton’s controversial views related to monetary policy and the Fed’s independence. But all 13 Republicans on the committee eventually said they wouldn’t hold up Shelton’s nomination and cleared the way for her to advance before the full Senate.

All 12 Democrats on the committee opposed Shelton’s nomination and called for a new hearing.