A Colorado Senate committee on Thursday approved a bill which would recognize the relationships of gay and lesbian couples with civil unions.

A 4-3 vote in favor of the measure sent it to the full Senate for consideration.

Thursday's vote was the second legislative victory for the bill which cleared the Senate Judiciary Committee last Wednesday along a 3-2 party-line vote. Civil unions legislation has failed in the two previous legislative sessions.

Christian conservative groups which oppose the measure, such as the Alliance Defending Freedom and CitizenLink, the political arm of Focus on the Family, have previously said that the measure threatens religious freedom.

Several have warned that the ultimate goal for Democrats is extending marriage rights to gay couples.

However, a constitutional amendment approved by voters in 2006 limits marriage to heterosexual couples.

With Democrats in control of both chambers and Governor John Hickenlooper a supporter, passage appears nearly assured.

If the bill is approved, Colorado would join 5 other states – Delaware, Illinois, New Jersey, Rhode Island and Hawaii – which offer the union. However, all 5 of those states, along with Minnesota, are expected to consider legalizing gay marriage this year.