The Conservative grassroots rebellion over plans to equalise laws to allow gay and lesbian couples to marry has moved up a step with a group of party constituency chairmen and longstanding supporters taking their protest to Downing Street. A letter signed by 22 current and former chairmen of local groups urges the prime minister to reconsider or at least delay the plans, which face a crucial vote this week.The Conservative grassroots rebellion over plans to equalise laws to allow gay and lesbian couples to marry has moved up a step with a group of party constituency chairmen and longstanding supporters taking their protest to Downing Street. A letter signed by 22 current and former chairmen of local groups urges the prime minister to reconsider or at least delay the plans, which face a crucial vote this week.