The US mid-term elections have seen the Republicans gain control of the lower house, while the Democrats held on to the Senate.

The Republicans won at least 60 House seats from the Democrats. In the Senate, the Democrats lost six seats.

According to commentators, the result presents both challenges and opportunities for gay rights.

Losing control of Congress may make it difficult for President Obama to repeal Don’t Ask, Don’t Tell in the next year, although gay campaigners said pro-gay candidates had been selected in four critical states where marriage equality is likely.

In one disappointment, Pennsylvania representative Patrick Murphy lost his seat. The former paratrooper was a strong advocate for repealing the ban on out gay soldiers.

However, another campaigner to repeal the ban, Kirsten Gilibrand, retained her Senate seat in New York. She told supporters last night that she would continue fighting for civil rights and an end to anti-gay policies.

In New York, gay marriage supporter Andrew Cuomo won the gubernatorial race against Republican rival Carl Paladino, who attacked Pride marches.

Democrat Jerry Brown won California’s gubernatorial race to succeed outgoing governor Arnold Schwarzenegger. Mr Brown, who was the state’s attorney-general, declined to defend the state’s gay marriage ban in court this year.

In the Florida senate race, governor Charlie Crist was beaten by Republican contender Marco Rubio. During his campaign, Mr Crist had reversed on much of his position on gay rights, promising a raft of new equality measures. Mr Rubio is a Tea Party candidate who is expected to hold conservative views on gay rights.

The US’ largest gay group, Human Rights Campaign, said that while an “anti-gay” Republican leadership in the House would impede federal legislative efforts, anti-gay candidates did not fare well against “fair-minded” opponents.

HRC president Joe Solmonese said: “Social justice movements always experience steps forward and steps back and this election turned out to be a mix of both.

“Even though we will face greater challenges in moving federal legislation forward, nothing will stop us from using every tool to advance LGBT equality at every level. Attempts to hold back the tide of the equality movement will surely put anti-LGBT leaders on the wrong side of history.”

But he added: “We will be prepared to fight attempts to turn back the clock on equality as well as highlight how far this new leadership is outside the mainstream of public opinion.”

Freedom to Marry said that victories in four states would bode well for marriage equality, including the election of new governors in New York and Rhode Island, the re-election of Martin O’Malley in Maryland, and Mark Dayton’s expected win in Minnesota.

Evan Wolfson, of Freedom to Marry, said: “Across the country, from New York to California, Americans cast their ballots for candidates who support marriage.

“A majority of the electorate supports the freedom to marry, and those fair-minded voters showed up at the polls and elected pro-marriage equality candidates, even in this otherwise tough political environment for progressive politicians.

“It is time for our elected officials to do the right thing and end government discrimination in marriage.”