date released      polling institute        socialist social democratic  peoples party green - communist     left bloc   lead
0   february 20 , 2005       election results  45.0% 121 seats    28.8% 75 seats  7.2% 12 seats     7.5% 14 seats  6.4% 8 seats  16.2%
1   february 18 , 2005                aximage            46.8%             29.6%           7.3%              7.0%          5.5%  17.2%
2   february 18 , 2005               marktest            46.0%             26.8%           7.5%              8.9%          7.7%  19.2%
3   february 18 , 2005           eurosondagem            45.0%             30.6%           7.7%              7.7%          5.7%  14.4%
4   february 18 , 2005                   ipom            46.0%             30.0%           8.0%              6.0%          7.0%  16.0%
5   february 18 , 2005            intercampus            45.9%             30.3%           7.1%              7.6%          5.2%  15.6%
6   february 17 , 2005        tns / euroteste            39.0%             28.0%           7.0%              6.0%          6.0%  11.0%
7   february 17 , 2005  universidade católica            46.0%             31.0%           6.0%              7.0%          7.0%  15.0%
8   february 12 , 2005           eurosondagem            44.4%             31.3%           7.4%              6.9%          6.4%  13.1%
9   february 11 , 2005                aximage            44.7%             27.4%           6.4%              7.1%          4.8%  17.3%
10   february 4 , 2005                   ipom            49.0%             31.0%           8.0%              6.0%          5.0%  18.0%
11   february 4 , 2005                aximage            43.5%             29.3%           7.0%              5.6%          3.5%  14.2%
12   february 3 , 2005            intercampus            46.5%             31.6%           4.8%              8.1%          4.5%  14.9%
13   january 29 , 2005           eurosondagem            46.1%             32.1%           7.0%              6.6%          4.6%  14.0%
14   january 28 , 2005               marktest            45.1%             27.7%           6.3%              7.7%          8.1%  17.5%
15   january 28 , 2005                aximage            43.3%             27.4%           6.3%              5.8%          5.0%  15.9%
16   january 28 , 2005  universidade católica            46.0%             28.0%           6.0%              8.0%          8.0%  18.0%
17   january 27 , 2005        tns / euroteste            40.0%             32.0%           6.0%              4.0%          5.0%   8.0%
18   january 21 , 2005                axiamge            42.8%             28.7%           7.1%              6.2%          4.3%  14.1%

Table as JSON:
{"date released":{"0":"february 20 , 2005","1":"february 18 , 2005","2":"february 18 , 2005","3":"february 18 , 2005","4":"february 18 , 2005","5":"february 18 , 2005","6":"february 17 , 2005","7":"february 17 , 2005","8":"february 12 , 2005","9":"february 11 , 2005","10":"february 4 , 2005","11":"february 4 , 2005","12":"february 3 , 2005","13":"january 29 , 2005","14":"january 28 , 2005","15":"january 28 , 2005","16":"january 28 , 2005","17":"january 27 , 2005","18":"january 21 , 2005"},"polling institute":{"0":"election results","1":"aximage","2":"marktest","3":"eurosondagem","4":"ipom","5":"intercampus","6":"tns \/ euroteste","7":"universidade católica","8":"eurosondagem","9":"aximage","10":"ipom","11":"aximage","12":"intercampus","13":"eurosondagem","14":"marktest","15":"aximage","16":"universidade católica","17":"tns \/ euroteste","18":"axiamge"},"socialist":{"0":"45.0% 121 seats","1":"46.8%","2":"46.0%","3":"45.0%","4":"46.0%","5":"45.9%","6":"39.0%","7":"46.0%","8":"44.4%","9":"44.7%","10":"49.0%","11":"43.5%","12":"46.5%","13":"46.1%","14":"45.1%","15":"43.3%","16":"46.0%","17":"40.0%","18":"42.8%"},"social democratic":{"0":"28.8% 75 seats","1":"29.6%","2":"26.8%","3":"30.6%","4":"30.0%","5":"30.3%","6":"28.0%","7":"31.0%","8":"31.3%","9":"27.4%","10":"31.0%","11":"29.3%","12":"31.6%","13":"32.1%","14":"27.7%","15":"27.4%","16":"28.0%","17":"32.0%","18":"28.7%"},"peoples party":{"0":"7.2% 12 seats","1":"7.3%","2":"7.5%","3":"7.7%","4":"8.0%","5":"7.1%","6":"7.0%","7":"6.0%","8":"7.4%","9":"6.4%","10":"8.0%","11":"7.0%","12":"4.8%","13":"7.0%","14":"6.3%","15":"6.3%","16":"6.0%","17":"6.0%","18":"7.1%"},"green - communist":{"0":"7.5% 14 seats","1":"7.0%","2":"8.9%","3":"7.7%","4":"6.0%","5":"7.6%","6":"6.0%","7":"7.0%","8":"6.9%","9":"7.1%","10":"6.0%","11":"5.6%","12":"8.1%","13":"6.6%","14":"7.7%","15":"5.8%","16":"8.0%","17":"4.0%","18":"6.2%"},"left bloc":{"0":"6.4% 8 seats","1":"5.5%","2":"7.7%","3":"5.7%","4":"7.0%","5":"5.2%","6":"6.0%","7":"7.0%","8":"6.4%","9":"4.8%","10":"5.0%","11":"3.5%","12":"4.5%","13":"4.6%","14":"8.1%","15":"5.0%","16":"8.0%","17":"5.0%","18":"4.3%"},"lead":{"0":"16.2%","1":"17.2%","2":"19.2%","3":"14.4%","4":"16.0%","5":"15.6%","6":"11.0%","7":"15.0%","8":"13.1%","9":"17.3%","10":"18.0%","11":"14.2%","12":"14.9%","13":"14.0%","14":"17.5%","15":"15.9%","16":"18.0%","17":"8.0%","18":"14.1%"}}