OLYMPIA — Gov. Chris Gregoire has approved a measure that will temporarily suspend the tax-limiting constraints placed on lawmakers by voter-approved Initiative 960. Gregoire signed the bill Wednesday afternoon, just days after the Legislature approved the measure. The bill spurred two weeks of heated debate in both the House and Senate. I-960 made it harder for lawmakers to raise taxes or to close tax exemptions, which is why the Democratic majority wanted it suspended. Budget writers want a mix of spending cuts, tax increases and one-time fixes to fill a $2.8 billion deficit. But I-960, approved in 2007, required two-thirds approval from legislators to raise taxes — a significant hurdle compared with the simple majority needed to pass other measures.