As Democrats begin their early-bird bids for the White House, the AFL-CIO is trying to regain lost political clout. The federation's political muscle has become a bit flabby in recent years as union members wavered from support of liberal Democrats to conservatism in voting booths. Now, says AFL-CIO, those who voted for President Reagan and other Republicans are disillusioned with their choices. One sign of the new campaign will be a heavy barrage of criticism of President Reagan and his administration, particularly on the unemployment issue. Despite the apparent slip in labor's clout, it remains a force to be reckoned with. A number of Democratic presidential hopefuls are expected to make ''courtesy calls'' at the AFL-CIO's midwinter executive council meeting on Feb. 21, seeking an AFL-CIO endorsement before the start of 1984 primary campaigns.
Even Republicans may try to ease current tensions between the GOP and labor.m