Tuesday could be a game changer for gay and lesbian couples who wish to tie the knot in Colorado.

Despite the fact that a majority of Coloradans (68%) support legal recognition of the relationships of gay couples, a civil unions law approved twice in the Colorado Senate has been blocked from passage in the Republican-led House. (A 2006 constitutional amendment bars marriage for gay couples.)

Tuesday could break that log jam, if Democrats regain control of the House.

Republicans are holding on to power with a slim one-seat majority. And with more than a half dozen competitive House races, the probability that Democrats will regain control is high.

Should Democrats return to power in the House, they could make history again on Thursday, the day the House Democratic Caucus picks its next leader. It could be Minority Leader Mark Ferrandino, who is openly gay.

In the Senate, Senator Pat Steadman could be elected Senate President, marking a legislative first for the nation: two openly gay men leading both state legislative chambers.

Steadman and Ferrandino are also the primary sponsors of the civil unions bill.

(Related: Nearly 70 percent of Coloradans back civil unions for gay couples.)