ST. PAUL (AP) — Minnesota business and labor union lobbies were among the heaviest spenders on lobbying during the first five months of 2013, which coincided with the Legislature's annual session.

A trio of business groups combined to spend more than $1.86 million, largely to counter proposals in the Democratic-dominated Capitol. On the flip side, several organizations lobbying for labor union proposals reported five- or six-figure spending.

The main groups on both sides of the gay marriage debate saw a disparity in spending. Minnesotans United for All Families spent about $1.6 million in a successful effort, which was far more than the $211,000 spent by opposition group Minnesota for Marriage.

The National Rifle Association spent roughly $100,000 in a session that produced only minor gun law changes. Gun control advocates put in far less.