Sen. Scott Brown (R-Mass.) will speak to Log Cabin Republicans and receive the organizations Spirit of Lincoln award Tuesday, a day that also marks the end of the longstanding ban on gays serving openly in the U.S. military.

The group, which represents gay and lesbian Republicans, is honoring Brown for his vote to end Dont Ask, Dont Tell, although the group said the timing of the dinner is coincidental. Although President Obama certified the repeal in July, it took two months to go into effect.

When a soldier answers the call to serve and risks life or limb, it has never mattered to me whether they are gay or straight, Brown will say, according to his prepared remarks. What matters is whether their service and sacrifice is with pride and honor.

Brown, who has served in the National Guard for more than three decades, will tell Log Cabin Republicans he entered the Senate in 2010 with an open mind on the issue, and after reviewing a Pentagon assessment that found a repeal would not adversely affect troop readiness, he decided to support a repeal.

The issue of gay rights is a delicate one for Brown, a Republican representing one of the most Democratic-leaning and socially progressive states in the nation. Brown appears headed for a serious reelection challenge in 2012, and has carefully avoided alienating either Massachusetts Democrats or national Republicans.

That caution is evident in Browns remarks to Log Cabin Republicans, where he will stop far short of calling out his fellow Republicans, almost all of whom voted to keep the ban in place.

I have found that there are good people on both sides of every issue and, even though we may come out on different sides sometimes, there are plenty of topics where we can find common ground, Brown will say.

Brown has not always been the darling of gay rights groups, and Democrats have seized the issue as a way to make the case that Brown is out of sync with Massachusetts residents on social issues.

Gay rights groups called Brown to task in July for refusing to participate in the It Gets Better video series, where prominent public figures offer support to gay teenagers in an attempt to cut down on suicide and depression.

Brown, the only Republican in Massachusetts’s 12-member congressional delegation, was also the only member of the delegation not to appear in the video.