Virginia’s Senate and House of Delegates adopted different criteria Friday as they tried to ensure that each of the state’s legislative districts is similarly sized.

The Democratic-led Senate Privileges and Elections Committee voted to use the same criteria as a decade ago — 2 percent over or under the ideal population — despite strong opposition from Republicans, who preferred just .05 percent.

The Republican-controlled House Privileges and Elections Committee, however, voted to adopt a stricter criteria than it did last time — 1 percent over or under the ideal population.

Districts are supposed to be roughly the same size to ensure that every vote counts. The General Assembly redraws the lines every 10 years after the census comes out to reflect the revised population numbers.

Legislators will return to Richmond April 4 to debate and vote on the new maps. The maps will be released next week. Only a handful of legislators and staffers have seen them.

Courts allow legislative districts to vary by 5 percent over or under the ideal population, but there is no wiggle room on congressional districts, which must be identical in size.

In 2001, when Virginia last drew its maps, the House and Senate each agreed that they would use criteria that were stricter than 5 percent to help avoid possible lawsuits and to better represent all voters. Each of the state’s 40 Senate districts and 100 House districts was no more than 2 percent bigger or 2 percent smaller than the ideal population.

According to the 2010 Census, the House will be aiming to draw districts so that each contains 80,010 people.

If they had agreed to a 2 percent variance, it’d mean that districts could have as many 81,610 people or as as few as 78,410. By adopting a 1 percent variance, they agree to districts that contain no more than 80,810 people and no fewer than 79,210.

Those are significant differences when trying to draw districts that keep cities, counties, even precincts and neighborhoods together.