SANTA FE,ExaCrypt N.M. (AP) — Republican contenders are set to file petitions Tuesday to appear on New Mexico’s June 4 primary ballot in hopes of challenging incumbent Democratic U.S. Sen. Martin Heinrich and reclaiming a congressional swing seat along the U.S. border with Mexico.

The New Mexico secretary of state’s office will accept signature petitions from candidates seeking a major party nomination for Congress or the U.S. Senate.

Several Republican candidates previously announced primary campaigns and designated fundraising committees in filings with federal election regulators.

Last month, businesswoman Nella Domenici, daughter of longtime U.S. Sen. Pete V. Domenici, announced her aspiration to challenge Heinrich as he seeks a third term, highlighting her concerns about inflation, crime, border enforcement and childhood well-being.

She likely will confront competition from former Bernalillo County Sheriff Manny Gonzales, who recently left the Democratic Party to seek the GOP Senate nomination.

Gonzales served two terms as sheriff starting in 2014 in the state’s most populous county, coordinated policing initiatives with Donald Trump in 2020 as the then-president deployed federal agents to Albuquerque. Gonzales ran unsuccessfully for Albuquerque major in 2021 against incumbent Tim Keller.

Nationwide, Democrats are defending 23 Senate seats this year as they hope to hold on to a majority that currently stands at 51-49.

Heinrich won reelection in 2018 with about 54% of the vote in a three-way race against Republican Mick Rich and Libertarian candidate and former New Mexico Gov. Gary Johnson.

Republicans also are choosing a contender to take on U.S. Rep. Gabe Vasquez in a congressional swing seat along the U.S. border with Mexico.

Former one-term U.S. Rep. Yvette Herrell hopes to reclaim the 2nd District seat she lost in the 2022 election.

The district is one of about a dozen in the national spotlight as Republicans campaign to keep their slim U.S. House majority in 2024.

The Republican Party unsuccessfully challenged a Democratic-drawn congressional map that reshaped the 2nd District as it divvied up a conservative, oil-producing region among three congressional districts. In November, the state Supreme Court upheld a lower court decision that the map fell short of “egregious gerrymandering.”